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Area forecast discussion...updated 
National Weather Service New Orleans la
1145 am CST Wednesday Nov 25 2015


Updated grids and forecast products to bump high temperatures up
about 5 degrees in most areas based on current trends. Cloud cover
is not as extensive as originally anticipated. 35


Previous discussion... /issued 313 am CST Wednesday Nov 25 2015/

generally only small adjustments made to the forecast with this
package. Surface high pressure will remain entrenched along the
East Coast with the ridge axis extending from the Carolinas toward
the central Gulf Coast. Winds will be easterly to southeasterly
which will continue to result in gradually warming temperatures
and increasing moisture.

As the pressure gradient tightens and east/southeasterly winds
strengthen...still expecting tides to rise up to 2 feet above
normal which could lead to minor inundation of the usual trouble
spots. Coastal Flood Advisory will remain in effect through at
least tonight.

00z guidance has come in slight chance probability of precipitation for portions of the
area today and this is supported by the latest short term high
resolution models as well. Already seeing a few showers over the
coastal waters...though not quite as many as the high res models
were suggesting for this time. Regardless...have gone ahead and
bumped probability of precipitation into the slight chance category for areas generally
along/south of the Interstate 10/12 border. In these areas...
marine showers could move inland with some light rainfall

By Thursday upper ridging becomes more established and should keep
shower activity to the north and west of the local area through
the end of the week. With the exception of this morning...expect
temperatures to be generally above normal through the end of the

Long term...
forecast going into the weekend and early next week continues to
be murky. Models continue to struggle with details of next frontal
system. Upper low still forecast to become cut off over California
or Nevada through the first part of the weekend. This should keep
frontal boundary well to our northwest through Saturday with no
significant precipitation locally. With every run seeming to come in just
a little bit slower than the last...have trended the extended
forecast toward slower solutions and have kept temperatures on the warmer
side of the guidance envelope. Looks like probability of precipitation will gradually
increase from west to east beginning Sunday. The front is
currently forecast to move through late Tuesday. Nothing much in
the way of will continue to leave thunder out of
the forecast. Temperatures should drop back to near normal behind the

VFR expected through this taf pack. But some ceilings will begin
lower today to around bkn030. Ceilings are expected to lower more
toward bkn015 by Thursday morning but that will be just outside this
package. Couple of showers will be around today but not enough to
mention for any one terminal but hum would be the most likely to see
any 10% or 20% coverage.

not much change in thinking in marine forecast. Have become more
concerned for coastal flooding impact as a persistent easterly
flow has prompted US to issue a coastal Flood Advisory as The
Tides and swells will cause some minor nuisance coastal flooding
impacts this week. High pressure over the Atlantic coast line will
be slow to move. A cold front will progress southeastward and
stall near Texarkana Friday. As this occurs...a strong pressure
gradient will build over the southern US and Gulf coastal waters.
Easterly winds will remain elevated through the week then shifting
to southeast into the weekend. The cold front may make it through
the area by next week. Will keep current flags and only minor
changes to ongoing fcast.

Decision support...
Activities...coastal Flood Advisory Wednesday night.
Small Craft Advisory through Thursday.
Monitoring minor flooding along Pearl River.

Decision support services (dss) code legend
green = no weather impacts that require action
blue = long fused watch/warning/advisory in effect or high
visibility event
yellow = heightened impacts with short fused watch/warning/advisory
issuances; radar support
Orange = high impacts - slight to moderate risk severe; nearby
tropical events; hazmat or other large episodes
red = full engagement for moderate risk severe and/or direct
tropical threats; events of National significance


Preliminary point temps/pops...
mcb 69 56 71 60 / 10 10 10 10
btr 74 61 74 62 / 10 10 10 10
asd 74 58 72 60 / 10 10 10 10
msy 72 63 74 64 / 20 10 20 10
gpt 73 59 71 60 / 10 10 10 10
pql 73 58 72 59 / 10 10 10 10


Lix watches/warnings/advisories...
la...coastal Flood Advisory until 6 am CST Thursday for laz040-050-

GM...Small Craft Advisory until 6 PM CST Thursday for gmz532-534-536-

Small Craft Advisory until 6 PM CST Thursday for gmz572-575-577.

MS...coastal Flood Advisory until 6 am CST Thursday for msz080>082.

GM...Small Craft Advisory until 6 PM CST Thursday for gmz534-536-538-

Small Craft Advisory until 6 PM CST Thursday for gmz575-577.



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